city, northern Ukraine. It was founded in the 1630s as a Polish defense outpost near the border with Russia. Ukrainian Cossacks (Cossack) controlled it from 1654 to 1781, after which it came under direct Russian administration. Rapid growth began in the early 20th century when the railway reached the city. Important industries have included railroad repair and the manufacture of machinery. The city is also a centre of technical education. Pop. (2005 est.) 90,961.